2 Inch Tig Pipe 2G help

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Running a scratch start setup on 2" sch 40 pipe horizontal, the cover pass should be one or two pass's.  My lead instructor says 2, but my other one with tons of pipe experience cringes when he sees i'm not running one pass.  I feel that from edge to edge of the weld is small enough to run one.  All the pipes are hand beveled around 40 degrees so it does vary a little. I can get some photos tomorrowThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:Who ever gives you the grade you should run what they want.. I seen it and done it both ways.. Which way do you like? I would practice running it both ways though..
Reply:I like to weave everywhere that I can.  It's because I'm lazy - then I don't have to plan for the size of the next pass That's why I like to weave uphill stick when it gets wide enough.ShortbusWelder is right though - we should both be practicing weave and stringers....Dave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:I prefer to knit and purl....Motorboating...in the Cleavage of the Tetons
Reply:battlelavaIf both one and/or two passes are accepted industrial standards; the two instructors have to agree on what they are teaching.I also had two instructors in welding school: one favored pornography, and the other one wanted to grow orchids, so the students got to weld any way they wanted. Student learners should not be subject to confusion: in the curriculum, or to professional jealousies  -  'tug o' wars'.It's awkward for a student to 'question authority', but get them togetherand casually ask for a clarification whether you learn/practice one pass,or two pass, for this joint configuration  -  or best, say you want to learn both.In offering to learn both, you have given your instructors a side-door - ineffect, you get an answer, and both instructors prevail.Opus
Reply:You want two welders to agree on who is right?  Seems like a tall order   LOLDave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:So far I have only done a 2 stringer cap so far. And I feel one cap would be easier, and more time effective out in the field.  The head man says they look good.  My roots I have the same delema one says feed from outside and push the wire in the joint the other says feed from the inside.   At least I managed to get rid of that blasted foot pedal. Nit to mention I've been tig welding pipe for 2 days nowThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:Well for some strange reason it wont let me edit my last post, so heres the pics i mentioned before.  These are the first ones I have done with tig pipe.  Go easy  gotta start somewhere. Attached ImagesThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:What size filler and tungsten you using? How many amps?   I would try a two stringer pass on that. Use the dab tech., instead of weaving..  You need a little more filler in the root too.  Grind/feather your tacks, and starts and stops.. You will get it though, it takes practice and time..  Thanks for the pics..
Reply:3/32 2% thoriated #17 air cooled 14cfh with #6 cup. Miller maxstar(I think) about 100 amps root and 110 on the cover. So far I've laywired everything. My roots looked better today.instructor said I had to get the wire into the root moreThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:Originally Posted by battlelava3/32 2% thoriated #17 air cooled 14cfh with #6 cup. Miller maxstar(I think) about 100 amps root and 110 on the cover. So far I've laywired everything. My roots looked better today.instructor said I had to get the wire into the root more
Reply:Originally Posted by MinnesotaDaveYou want two welders to agree on who is right?  Seems like a tall order   LOL
Reply:If you like to learn from videos, Jody at weldingtipsandtricks.com has videos with TIG pipe.The arc shots are nice and clear.  This one is 2" sch 80.[ame]http://www.youtube.com/watch?v=bBXjRS4e6PA[/ame]Dave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:I have complete control on heat. I had it at about 75 before and it didn't penetrate at all. Ill I'm running slightly bigger then 3/32 gap with like 1/16 land. If its that big.  I have watched Jody's video on that 2" pipe many times. Outside looks the same but penetration is all over the place.They call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:On flat plate I had inconsistent penetration when I started learning tig.  It was due to me not watching the keyhole happen on each movement forward of the torch.  I was just adding filler and moving in a rhythm. Fixed it when I did, move, keyhole, add filler, move, keyhole, add filler...etc.I have not tried it on pipe yet - maybe a similar issue for you?Dave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:Originally Posted by battlelavaI have complete control on heat. I had it at about 75 before and it didn't penetrate at all. Ill I'm running slightly bigger then 3/32 gap with like 1/16 land. If its that big.  I have watched Jody's video on that 2" pipe many times. Outside looks the same but penetration is all over the place.
Reply:Dave. I have done open root on 1/8 plate with good results. Had the heat up high and moved pritty quickly. I have tryed feeding from the back. I don't really have a clue how your suppose to but I just went to the next tack to rest the wire on and pushed/fed it into the puddleThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:Heres some disgusting results from today.  lost my head rather quickly today and couldnt get anything to work.   Was all over the place.  As you can see I couldn't even get my t joint to stay consistent in size today.   I'll just try again tomorrow Attached ImagesThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:you need to clean your parts. most especially the inside of the pipe, use a pencil grinder or even a file if you have to. everything will look better without all that junk floating around in your puddle. you can't TIG over rust. clean it to shiny metal back at least a quarter inch inside and out.Last edited by TimmyTIG; 04-19-2013 at 05:38 AM.
Reply:Originally Posted by battlelavaI have complete control on heat. I had it at about 75 before and it didn't penetrate at all. Ill I'm running slightly bigger then 3/32 gap with like 1/16 land. If its that big.  I have watched Jody's video on that 2" pipe many times. Outside looks the same but penetration is all over the place.
Reply:2 inch schedule 40 is tough even for an experienced welder. It heats up so fast it's tough to keep up. see if you can find some schedule 80 to practice on.
Reply:Originally Posted by TimmyTIG2 inch schedule 40 is tough even for an experienced welder. It heats up so fast it's tough to keep up. see if you can find some schedule 80 to practice on.
Reply:Yes, clean your pipes very good..  Second, your weaves look really big for 3/32.. I would tighten them up, but that's me.. Third, you walking the cup, or free handing it?To help keep the heat down, start at the top of the pipe, this way the heat isn't rising up the sides of the pipe to the top.. Also quarter your pip when welding if it's getting too hot for you..  It's not a race to weld these pipes out, just don't take all day.. lol.With lay tech, are you washing the filler rod up on the sides of the pipe, of just going back and forth real quick?? Try to wash it up more on the sides, while feeding more wire.Keep a calm head, if you get frustrated, go and grab drink and take a break..  Is your lens clear on your hood, can't weld if you can't see///
Reply:3/32 on that?I would be using .040 but that's just me....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Well it was time to cut up some new pipe and i grabbed the wrong size   Grabbed some 1 1/2 by mistake instead of the 2".  Only thing was it looked 10x better then the 2" ive been doing.  Root had good penetration, cap looked somewhat decent (although the pictures don't make it look that great)  I did get alittle bit of wire stuck up in the root though Attached ImagesThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeterDid a couple coupons, maybe it'll help you.  I found using 3/32 filler on the root, my natural instinct was to fill the bevel almost flush.  This involves being able to feed pretty accurately, 4" of filler for 1" of root opening.....85 amps, 3/32 gap, scratch start.....If traveling  left to right, feed to lower edge of top  bevel.  swing arc to bottom as in backwards 'D', straight up, feed again.     This is pretty tricky for a newbie, but it's something to eventually learn because there will be times when your gap will vary and the 3/32 let's you play around a little.   For perfect fit-up use lay technique with 1/8" filler.  It's a lot easier.  Sloppy 3/32" gap, 80-85 amps,  just make sure to keep slight pressure on end of filler.  Sharp tungsten.  While advancing just fast enough that you see the filler start to melt, arc motion is from inside top of filler, hold momentarily till it wets out, down to bottom inside of filler...call it a very slight 'w' motion. For one pass cap, feed to upper third of weld, build up slightly higher then bevel edge, swing 'D' fashion to bottom and straight up.  This works pretty good in this circumstance but if the fill area was wider, you would have to add more material at center to get proper build-up.  As for pics, first two are 3/32 root. then 2 with 1/8" root.  Notice how much smaller the bead is with the 1/8" lay-wire technique.  Nicer root too. Attached ImagesLast edited by OldSparks; 04-20-2013 at 07:33 PM.
Reply:Got a few pics of some more that i did.  He has me doing some vertical. Idk why I know i can use more practice on horizontal. Anyway, To bad my chop saw took a dump on me and i can't cut the rest open to show the root.  Vert root had some stubs of wire stuck in it.  Probably not holding the wire up on the leading edge of the puddle?  Cap looked gross to me even though he said wasnt to bad for my first one.To be honest  none of them really look good at all.  Better then not getting to pipe.  Most students at my school never get near it.  Going for an pipe fitters apprenticeship soon, maybe they can help me lol Attached ImagesThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:That's pretty good for a green rookie. You keep at it, you'll get it. Welding takes tons of practice. Notice how bad that last one undercutted because you didn't clean it like you did the first one.You still have a lot of trash on top of your weld, even the first one. Clean it up better and most of that will go away. You have to clean all that crap off of there between passes, too. Looks like you cleaned the outside of the pipe on the first one, but not the inside.I realize you're probably anxious to get straight to welding, but you really need to clean it first.Last edited by TimmyTIG; 04-23-2013 at 05:32 AM.
Reply:Originally Posted by TimmyTIGThat's pretty good for a green rookie. You keep at it, you'll get it. Welding takes tons of practice. Notice how bad that last one undercutted because you didn't clean it like you did the first one.You still have a lot of trash on top of your weld, even the first one. Clean it up better and most of that will go away. You have to clean all that crap off of there between passes, too. Looks like you cleaned the outside of the pipe on the first one, but not the inside.I realize you're probably anxious to get straight to welding, but you really need to clean it first.
Reply:Results from today.  Don't look any better to me. Root may look a tad bit better, alot of wire stubs.  Kinda hard for me to not get it to stick still.  And my Instructor gave me this 1.5" XXH walled pipe to try out.  He said he wasn't gonna use it so he told me to give it  a shot. Roughly 80 Amps on the root  still using #6 cup with 3/32 red  #17 Air cooled torch scratch start.  Cover might have an extra 2-3 amps   I Don't know why im getting so much undercut. Maybe moving faster then i can get the filler to fill it up? Attached ImagesThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:As said before, you should really take your time and clean that pipe. Don't you have a grinder to clean the bevel and some of the outside of the pipe?Yes, your cap is a little rough.  You letting the pipe cool some before you do your cap? IF not, let it cool a bit.  Second, I would run to stringers on that cap, not one, this way you're not carrying all that filler metal from side to side..  You need to spend more time on the edges of your welds, not in the middle..  You filing your tacks on the root pass of the pipe? If not, do so, if so, good job.. Try to shrink your gap up on the root, and see how that goes..  What you running your hot pass at?  Don't go too hot, or you will get suck back..
Reply:I have a grinder I use on the outside of the pipe. I try to clean theinside with my file. I need to get a small sanding drum on a rotoary tool to clean that inside.  I let the pipe cool til I can touch it before I put any more pass's. Usual the cap is the hot pass. I'm going to try filling it a bit more before I cap it today.   I run it all the way out at 80-85 amps. I feather my tacks with my file.  On the root. Is the inside suppose to have this cut line on each side of the bead (on the inside of the pipe )They call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:Originally Posted by battlelavaI have a grinder I use on the outside of the pipe. I try to clean theinside with my file. I need to get a small sanding drum on a rotoary tool to clean that inside.  I let the pipe cool til I can touch it before I put any more pass's. Usual the cap is the hot pass. I'm going to try filling it a bit more before I cap it today.   I run it all the way out at 80-85 amps. I feather my tacks with my file.  On the root. Is the inside suppose to have this cut line on each side of the bead (on the inside of the pipe )
Reply:In a crunch you can get by using emery paper on the inside.  For the undercut....narrow the width of your torch movement and feed more when you are at the edge of the bead.  The filler should 'balloon' out beyond your arc. Are you allowed/have you tried 1/8" filler for root?  Less feeding, less room for error.  At 6 o'clock, keep arc inside filler width,edge to edge, similar to 2G 'w'.  Feed enough wire to appear convex on outside.  At 3 and 9 o'clock, your weave should be approximately half way up the bevel on each side.  Feed less wire.  Bead will appear flat from outside.By 12 o'clock, just lay wire and your weave should extend further up the bevel on each side.  This allows the weld to cool a bit and prevents too much penetration.  Bead will appear concave from outside.Pics show root at 6 o'clock.Note....these instructions are aimed at the thinner sch. 40  wall thickness and 9 to 3 o'clock root would involve less weave on the heavier wall. Attached ImagesLast edited by OldSparks; 04-25-2013 at 12:42 AM.
Reply:Found this picture.  It shows the change in bead profile described in the comment above.  Convex at 6 o'clock adjacent to the soapstone  line.  Flattens out at 9 o'clock, the top of the picture, Attached Images
Reply:I know it sounds counter intuitive but undercutting in your case is probably because of too low current. Try bumping the amps to 115-120A on the cap and move faster. With 80A the weld pool is not big enough to flow to the edge of bevel and you have to move the arc to the edge to get fusion which leads to undercutting.Try this and tell us how it turns out.
Reply:Originally Posted by OldSparksFound this picture.  It shows the change in bead profile described in the comment above.  Convex at 6 o'clock adjacent to the soapstone  line.  Flattens out at 9 o'clock, the top of the picture,
Reply:Originally Posted by ShortbusWelderThe edges need to be held a tad bit longer. Need to get more weld up on the edges..  Maybe a little cold too, the weld should be smoother..
Reply:I don't have any 1/8 wire. My lwi goes by if its big enough to use 1/8 wire you should stick weld it. I haven't had time to do any more tig pipe because I'm working on that 1.5xxh still. I rigged 3 passes and stick welded the rest out 7018 1/8 all the way out. Root looked good except one little nub on my hard side. I did it in 6g just because I figured only have one might as well go all out. The stick portion went great til the cap and I screwed up big time.                   Don't even know what I was doing. Gonna grind it out and try again ran the root with 1/8 gap 3/32 wire 90-95 amps. Hot the same then bumped up to 120ish on my phone right now or I'd add photoskoThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:Originally Posted by battlelavaI don't have any 1/8 wire. My lwi goes by if its big enough to use 1/8 wire you should stick weld it
Reply:Originally Posted by OldSparksInteresting comment....answers a lot of questions
Reply:Originally Posted by OldSparksInteresting comment....answers a lot of questions
Reply:The root looked good until I got forced into using 1/8th 7018 to soon.  Didn't have enough meat in there for me to get that learning curve of small pipe so i pushed my root into the pipe in 2 (on the left side top, the one on the right is a wire stub)spots.  And before someone jumps on my cover pass, ive only been welding 6 months  I'm in a structural plate course and when your done if you have time you can do some pipe, and this is the first pipe under 6" i've stick welded and it was done in 6g.  Cap pass's are 1)top 2)hard side 3)bottom 4)easier sideI know its not pretty, but the welds are pretty tight and i feel like i did a good job for my first time, and i know its a hell of a lot better then what i screwed up yesterday  This was 3/32 7018 at about 95-100 amps 35% dig Attached ImagesThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:Any thoughts on it?They call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:Decent enough effort.  I'm sure you learned a lot.  Awkward size pipe in that although the wall thickness is there to handle 1/8 for fill, whether the short distance is at all worth it.  I think a lot of people would fill with 3/32 and only use 1/8 for cap.  Others would all out with 3/32. Good practice when you have a piece of scrap pipe is to carry on capping out.  Use a wrap-a-round to draw a soapstone line about a half inch above your last pass and then try to run a pass that will parallel  out a little better then the one you're lapping.  A little slower here, a little faster there,  run a foot of cap and you'll only get better.  Carry on.
Reply:OldSparks - I like that idea of practicing caps on the outside of a scrap pipe - good idea Welding is a lot of muscle memory and seeing the same thing over and over...Dave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:I definitely learned a lot. I know the cap isn't straight because when I ground thenasty cap out I made the mistake of grinding to far out on 2 spots. Not saying it as an excuse because I should of fixed it properly. Surprisingly the top of the pipe looks the best even though I was all wrapped the pipe holding up the pipe I was welding  . Was a great learning experience as I've never done it beforeThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:With 2" sced 40 I use a big gap and backfeed my root in. Heck with all thicknesses I try to backfeed. With that sced 40 I would do a 2-3 bead 3/32 tig cap on it to make it look uniform.With that heavy wall I especially use a big gap and backfeed. With that size pipe use 1/8th wire. For the stick cap try a 4-5 bead stringer.With Tig you gotta die grinder with a flapper wheel on the inside/bevel and 1" back from the bevel on the pipe. If you don't clean 1" on the pipe itself you will get that undercut.
Reply:Well i got my hands on some 1/8th tig wire.  Apparently he had some after all.  did a 6" sch 40 pipe in 5g.  Root was hair under 1/8th with 1/8th filler and about 100-105 amps.  Had a little lack of fusion when i didn't turn the heat up enough.   1/8th on the hot pass with maybe 5 more amps.  ran in hot and i layed a huge hot pass, almost filling the pipe.  Don't know if i should have done such a big pass.  Not to mention i did one half the pipe walking and the other free handing (thanks to the tig finger)  Next pass and cover where at 135-140 amps and 1/8th filler.  Dang that #17 air cooled gets hot, even with stick glove on my one hand, only felt it when i free handed though.  Know there's a little undercut but i feel like its a huge improvement.  What do you guys think.. Note i did clean the outside and inside and the rust on the outside was from dunking it at the end of the day and i did clean it off before continuing. Attached ImagesThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter
Reply:Some more pictures,  Third is freehand and forth should be walking the cup. When i though it was done it was better looking  but i had a blob of porosity on the bottom and it was about 1/32 below flush so i ground out the porosity pushed the tungsten back in alittle and try agained. last photo is the bottom.  I can't believe i got so much undercut since the pass before that was fine. Attached ImagesThey call me ... youtube1979 SA 200 RED seal w/ wp26RealGear Mig 140Linde AC 250 Amp StickLincoln AC/DC 225 buzz box w/ #9 flex scratch start Smith precision tig flowmeter